h_generator.py revision 2385ea399aae016c0806a4f9ef3c9cfe3d2a39df
1# Copyright (c) 2012 The Chromium Authors. All rights reserved. 2# Use of this source code is governed by a BSD-style license that can be 3# found in the LICENSE file. 4 5from code import Code 6from model import PropertyType, Type 7import cpp_util 8import schema_util 9 10class HGenerator(object): 11 def __init__(self, type_generator, cpp_namespace): 12 self._type_generator = type_generator 13 self._cpp_namespace = cpp_namespace 14 15 def Generate(self, namespace): 16 return _Generator(namespace, 17 self._type_generator, 18 self._cpp_namespace).Generate() 19 20class _Generator(object): 21 """A .h generator for a namespace. 22 """ 23 def __init__(self, namespace, cpp_type_generator, cpp_namespace): 24 self._namespace = namespace 25 self._type_helper = cpp_type_generator 26 self._cpp_namespace = cpp_namespace 27 self._target_namespace = ( 28 self._type_helper.GetCppNamespaceName(self._namespace)) 29 30 def Generate(self): 31 """Generates a Code object with the .h for a single namespace. 32 """ 33 c = Code() 34 (c.Append(cpp_util.CHROMIUM_LICENSE) 35 .Append() 36 .Append(cpp_util.GENERATED_FILE_MESSAGE % self._namespace.source_file) 37 .Append() 38 ) 39 40 ifndef_name = cpp_util.GenerateIfndefName(self._namespace.source_file_dir, 41 self._target_namespace) 42 (c.Append('#ifndef %s' % ifndef_name) 43 .Append('#define %s' % ifndef_name) 44 .Append() 45 .Append('#include <map>') 46 .Append('#include <string>') 47 .Append('#include <vector>') 48 .Append() 49 .Append('#include "base/basictypes.h"') 50 .Append('#include "base/logging.h"') 51 .Append('#include "base/memory/linked_ptr.h"') 52 .Append('#include "base/memory/scoped_ptr.h"') 53 .Append('#include "base/values.h"') 54 .Cblock(self._type_helper.GenerateIncludes()) 55 .Append() 56 ) 57 58 c.Concat(cpp_util.OpenNamespace(self._cpp_namespace)) 59 # TODO(calamity): These forward declarations should be #includes to allow 60 # $ref types from other files to be used as required params. This requires 61 # some detangling of windows and tabs which will currently lead to circular 62 # #includes. 63 forward_declarations = ( 64 self._type_helper.GenerateForwardDeclarations()) 65 if not forward_declarations.IsEmpty(): 66 (c.Append() 67 .Cblock(forward_declarations) 68 ) 69 70 c.Concat(self._type_helper.GetNamespaceStart()) 71 c.Append() 72 if self._namespace.properties: 73 (c.Append('//') 74 .Append('// Properties') 75 .Append('//') 76 .Append() 77 ) 78 for property in self._namespace.properties.values(): 79 property_code = self._type_helper.GeneratePropertyValues( 80 property, 81 'extern const %(type)s %(name)s;') 82 if property_code: 83 c.Cblock(property_code) 84 if self._namespace.types: 85 (c.Append('//') 86 .Append('// Types') 87 .Append('//') 88 .Append() 89 .Cblock(self._GenerateTypes(self._FieldDependencyOrder(), 90 is_toplevel=True, 91 generate_typedefs=True)) 92 ) 93 if self._namespace.functions: 94 (c.Append('//') 95 .Append('// Functions') 96 .Append('//') 97 .Append() 98 ) 99 for function in self._namespace.functions.values(): 100 c.Cblock(self._GenerateFunction(function)) 101 if self._namespace.events: 102 (c.Append('//') 103 .Append('// Events') 104 .Append('//') 105 .Append() 106 ) 107 for event in self._namespace.events.values(): 108 c.Cblock(self._GenerateEvent(event)) 109 (c.Concat(self._type_helper.GetNamespaceEnd()) 110 .Concat(cpp_util.CloseNamespace(self._cpp_namespace)) 111 .Append('#endif // %s' % ifndef_name) 112 .Append() 113 ) 114 return c 115 116 def _FieldDependencyOrder(self): 117 """Generates the list of types in the current namespace in an order in which 118 depended-upon types appear before types which depend on them. 119 """ 120 dependency_order = [] 121 122 def ExpandType(path, type_): 123 if type_ in path: 124 raise ValueError("Illegal circular dependency via cycle " + 125 ", ".join(map(lambda x: x.name, path + [type_]))) 126 for prop in type_.properties.values(): 127 if (prop.type_ == PropertyType.REF and 128 schema_util.GetNamespace(prop.ref_type) == self._namespace.name): 129 ExpandType(path + [type_], self._namespace.types[prop.ref_type]) 130 if not type_ in dependency_order: 131 dependency_order.append(type_) 132 133 for type_ in self._namespace.types.values(): 134 ExpandType([], type_) 135 return dependency_order 136 137 def _GenerateEnumDeclaration(self, enum_name, type_): 138 """Generate the declaration of a C++ enum. 139 """ 140 c = Code() 141 c.Sblock('enum %s {' % enum_name) 142 c.Append(self._type_helper.GetEnumNoneValue(type_) + ',') 143 for value in type_.enum_values: 144 c.Append(self._type_helper.GetEnumValue(type_, value) + ',') 145 return c.Eblock('};') 146 147 def _GenerateFields(self, props): 148 """Generates the field declarations when declaring a type. 149 """ 150 c = Code() 151 needs_blank_line = False 152 for prop in props: 153 if needs_blank_line: 154 c.Append() 155 needs_blank_line = True 156 if prop.description: 157 c.Comment(prop.description) 158 # ANY is a base::Value which is abstract and cannot be a direct member, so 159 # we always need to wrap it in a scoped_ptr. 160 is_ptr = prop.optional or prop.type_.property_type == PropertyType.ANY 161 (c.Append('%s %s;' % ( 162 self._type_helper.GetCppType(prop.type_, is_ptr=is_ptr), 163 prop.unix_name)) 164 ) 165 return c 166 167 def _GenerateType(self, type_, is_toplevel=False, generate_typedefs=False): 168 """Generates a struct for |type_|. 169 170 |is_toplevel| implies that the type was declared in the "types" field 171 of an API schema. This determines the correct function 172 modifier(s). 173 |generate_typedefs| controls whether primitive types should be generated as 174 a typedef. This may not always be desired. If false, 175 primitive types are ignored. 176 """ 177 classname = cpp_util.Classname(schema_util.StripNamespace(type_.name)) 178 c = Code() 179 180 if type_.functions: 181 # Wrap functions within types in the type's namespace. 182 (c.Append('namespace %s {' % classname) 183 .Append() 184 ) 185 for function in type_.functions.values(): 186 c.Cblock(self._GenerateFunction(function)) 187 c.Append('} // namespace %s' % classname) 188 elif type_.property_type == PropertyType.ARRAY: 189 if generate_typedefs and type_.description: 190 c.Comment(type_.description) 191 c.Cblock(self._GenerateType(type_.item_type)) 192 if generate_typedefs: 193 (c.Append('typedef std::vector<%s > %s;' % ( 194 self._type_helper.GetCppType(type_.item_type), 195 classname)) 196 ) 197 elif type_.property_type == PropertyType.STRING: 198 if generate_typedefs: 199 if type_.description: 200 c.Comment(type_.description) 201 c.Append('typedef std::string %(classname)s;') 202 elif type_.property_type == PropertyType.ENUM: 203 if type_.description: 204 c.Comment(type_.description) 205 c.Sblock('enum %(classname)s {') 206 c.Append('%s,' % self._type_helper.GetEnumNoneValue(type_)) 207 for value in type_.enum_values: 208 c.Append('%s,' % self._type_helper.GetEnumValue(type_, value)) 209 # Top level enums are in a namespace scope so the methods shouldn't be 210 # static. On the other hand, those declared inline (e.g. in an object) do. 211 maybe_static = '' if is_toplevel else 'static ' 212 (c.Eblock('};') 213 .Append() 214 .Append('%sstd::string ToString(%s as_enum);' % 215 (maybe_static, classname)) 216 .Append('%s%s Parse%s(const std::string& as_string);' % 217 (maybe_static, classname, classname)) 218 ) 219 elif type_.property_type in (PropertyType.CHOICES, 220 PropertyType.OBJECT): 221 if type_.description: 222 c.Comment(type_.description) 223 (c.Sblock('struct %(classname)s {') 224 .Append('%(classname)s();') 225 .Append('~%(classname)s();') 226 ) 227 if type_.origin.from_json: 228 (c.Append() 229 .Comment('Populates a %s object from a base::Value. Returns' 230 ' whether |out| was successfully populated.' % classname) 231 .Append('static bool Populate(const base::Value& value, ' 232 '%(classname)s* out);') 233 ) 234 if is_toplevel: 235 (c.Append() 236 .Comment('Creates a %s object from a base::Value, or NULL on ' 237 'failure.' % classname) 238 .Append('static scoped_ptr<%(classname)s> ' 239 'FromValue(const base::Value& value);') 240 ) 241 if type_.origin.from_client: 242 value_type = ('base::Value' 243 if type_.property_type is PropertyType.CHOICES else 244 'base::DictionaryValue') 245 (c.Append() 246 .Comment('Returns a new %s representing the serialized form of this ' 247 '%s object.' % (value_type, classname)) 248 .Append('scoped_ptr<%s> ToValue() const;' % value_type) 249 ) 250 if type_.property_type == PropertyType.CHOICES: 251 # Choices are modelled with optional fields for each choice. Exactly one 252 # field of the choice is guaranteed to be set by the compiler. 253 c.Cblock(self._GenerateTypes(type_.choices)) 254 c.Append('// Choices:') 255 for choice_type in type_.choices: 256 c.Append('%s as_%s;' % ( 257 self._type_helper.GetCppType(choice_type, is_ptr=True), 258 choice_type.unix_name)) 259 else: 260 properties = type_.properties.values() 261 (c.Append() 262 .Cblock(self._GenerateTypes(p.type_ for p in properties)) 263 .Cblock(self._GenerateFields(properties))) 264 if type_.additional_properties is not None: 265 # Most additionalProperties actually have type "any", which is better 266 # modelled as a DictionaryValue rather than a map of string -> Value. 267 if type_.additional_properties.property_type == PropertyType.ANY: 268 c.Append('base::DictionaryValue additional_properties;') 269 else: 270 (c.Cblock(self._GenerateType(type_.additional_properties)) 271 .Append('std::map<std::string, %s> additional_properties;' % 272 cpp_util.PadForGenerics( 273 self._type_helper.GetCppType(type_.additional_properties, 274 is_in_container=True))) 275 ) 276 (c.Eblock() 277 .Append() 278 .Sblock(' private:') 279 .Append('DISALLOW_COPY_AND_ASSIGN(%(classname)s);') 280 .Eblock('};') 281 ) 282 return c.Substitute({'classname': classname}) 283 284 def _GenerateEvent(self, event): 285 """Generates the namespaces for an event. 286 """ 287 c = Code() 288 # TODO(kalman): use event.unix_name not Classname. 289 event_namespace = cpp_util.Classname(event.name) 290 (c.Append('namespace %s {' % event_namespace) 291 .Append() 292 .Concat(self._GenerateEventNameConstant(event)) 293 .Concat(self._GenerateCreateCallbackArguments(event)) 294 .Eblock('} // namespace %s' % event_namespace) 295 ) 296 return c 297 298 def _GenerateFunction(self, function): 299 """Generates the namespaces and structs for a function. 300 """ 301 c = Code() 302 # TODO(kalman): Use function.unix_name not Classname here. 303 function_namespace = cpp_util.Classname(function.name) 304 """Windows has a #define for SendMessage, so to avoid any issues, we need 305 to not use the name. 306 """ 307 if function_namespace == 'SendMessage': 308 function_namespace = 'PassMessage' 309 (c.Append('namespace %s {' % function_namespace) 310 .Append() 311 .Cblock(self._GenerateFunctionParams(function)) 312 ) 313 if function.callback: 314 c.Cblock(self._GenerateFunctionResults(function.callback)) 315 c.Append('} // namespace %s' % function_namespace) 316 return c 317 318 def _GenerateFunctionParams(self, function): 319 """Generates the struct for passing parameters from JSON to a function. 320 """ 321 if not function.params: 322 return Code() 323 324 c = Code() 325 (c.Sblock('struct Params {') 326 .Append('static scoped_ptr<Params> Create(const base::ListValue& args);') 327 .Append('~Params();') 328 .Append() 329 .Cblock(self._GenerateTypes(p.type_ for p in function.params)) 330 .Cblock(self._GenerateFields(function.params)) 331 .Eblock() 332 .Append() 333 .Sblock(' private:') 334 .Append('Params();') 335 .Append() 336 .Append('DISALLOW_COPY_AND_ASSIGN(Params);') 337 .Eblock('};') 338 ) 339 return c 340 341 def _GenerateTypes(self, types, is_toplevel=False, generate_typedefs=False): 342 """Generate the structures required by a property such as OBJECT classes 343 and enums. 344 """ 345 c = Code() 346 for type_ in types: 347 c.Cblock(self._GenerateType(type_, 348 is_toplevel=is_toplevel, 349 generate_typedefs=generate_typedefs)) 350 return c 351 352 def _GenerateCreateCallbackArguments(self, function): 353 """Generates functions for passing parameters to a callback. 354 """ 355 c = Code() 356 params = function.params 357 c.Cblock(self._GenerateTypes((p.type_ for p in params), is_toplevel=True)) 358 359 declaration_list = [] 360 for param in params: 361 if param.description: 362 c.Comment(param.description) 363 declaration_list.append(cpp_util.GetParameterDeclaration( 364 param, self._type_helper.GetCppType(param.type_))) 365 c.Append('scoped_ptr<base::ListValue> Create(%s);' % 366 ', '.join(declaration_list)) 367 return c 368 369 def _GenerateEventNameConstant(self, event): 370 """Generates a constant string array for the event name. 371 """ 372 c = Code() 373 c.Append('extern const char kEventName[]; // "%s.%s"' % ( 374 self._namespace.name, event.name)) 375 c.Append() 376 return c 377 378 def _GenerateFunctionResults(self, callback): 379 """Generates namespace for passing a function's result back. 380 """ 381 c = Code() 382 (c.Append('namespace Results {') 383 .Append() 384 .Concat(self._GenerateCreateCallbackArguments(callback)) 385 .Append('} // namespace Results') 386 ) 387 return c 388